The paper investigates patterns of differences of some key economic and financial variables among U.S. regions. The grouping of the states into regions is in accordance with the Bureau of Economic Analysis classification (New England, Mideast, Great Lakes, Plains, Southeast, Southwest, Rocky...

This note utilizes a cubic polynomial to model the cyclical behaviour of income inequality in the U.S. from 1947 to 2000. Linear and quadratic models have been used to explain the pattern, but they are not capable of detecting more than one extreme point. The simplest model capable of detecting...